Mention the addition of VC{11,12} solution files in the change log.

This is an important thing for a lot of people.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@75927 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775